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201.
Cristina Colom David Viladés Montserrat Pérez-Cuellar Rubén Leta Andrea Rivas-Urbina Gemma Carreras Jordi Ordóñez-Llanos Antonio Pérez Jose Luis Sánchez-Quesada 《Cardiovascular diabetology》2018,17(1):156
Background
The pathophysiology of cardiovascular complications in people with type 1 diabetes (T1DM) remains unclear. An increase in epicardial adipose tissue (EAT) and alterations in the composition of high-density lipoprotein (HDL) are associated with coronary artery disease, but information on its relationship in T1DM is very limited. Our aim was to determine the association between EAT volume, subclinical atherosclerosis, and HDL composition in type 1 diabetes.Methods
Seventy-two long-term patients with T1DM without clinical atherosclerosis were analyzed. EAT volume and subclinical atherosclerosis were measured using cardiac computed tomography angiography. EAT was adjusted according to body surface to obtain an EAT index (iEAT). HDL composition was determined.Results
The mean iEAT was 40.47?±?22.18 cc/m2. The bivariate analysis showed positive associations of the iEAT with gender, age, hypertension, dyslipidemia, smoking, body mass index, waist circumference, insulin dose, and triglyceride (P?<?0.05). The iEAT correlated positively with small HDL, increased content of apolipoprotein (apo)A-II and apoC-III, and decreased content of apoE and free cholesterol. Multiple linear regression showed that age, apoA-II content in HDL, and waist circumference were independently associated with the iEAT. Fifty percent of the patients presented subclinical atherosclerotic lesions. These patients had a higher iEAT, and their HDL contained less cholesterol and more apoA-II and lipoprotein-associated phospholipase A2 than patients without subclinical atherosclerosis.Conclusion
Alterations in the composition of HDL in TIDM are associated with increased iEAT and the presence of subclinical atherosclerosis. We propose that these abnormalities of HDL composition could be useful to identify T1DM patients at highest cardiovascular risk.202.
High‐resolution mapping of the recombination landscape of the phytopathogen Fusarium graminearum suggests two‐speed genome evolution 下载免费PDF全文
Benoit Laurent Christos Palaiokostas Cathy Spataro Magalie Moinard Enric Zehraoui Ross D. Houston Marie Foulongne‐Oriol 《Molecular Plant Pathology》2018,19(2):341-354
Recombination is a major evolutionary force, increasing genetic diversity and permitting efficient coevolution of fungal pathogen(s) with their host(s). The ascomycete Fusarium graminearum is a devastating pathogen of cereal crops, and can contaminate food and feed with harmful mycotoxins. Previous studies have suggested a high adaptive potential of this pathogen, illustrated by an increase in pathogenicity and resistance to fungicides. In this study, we provide the first detailed picture of the crossover events occurring during meiosis and discuss the role of recombination in pathogen evolution. An experimental recombinant population (n = 88) was created and genotyped using 1306 polymorphic markers obtained from restriction site‐associated DNA sequencing (RAD‐seq) and aligned to the reference genome. The construction of a high‐density linkage map, anchoring 99% of the total length of the reference genome, allowed the identification of 1451 putative crossovers, positioned at a median resolution of 24 kb. The majority of crossovers (87.2%) occurred in a relatively small portion of the genome (30%). All chromosomes demonstrated recombination‐active sections, which had a near 15‐fold higher crossover rate than non‐active recombinant sections. The recombination rate showed a strong positive correlation with nucleotide diversity, and recombination‐active regions were enriched for genes with a putative role in host–pathogen interaction, as well as putative diversifying genes. Our results confirm the preliminary analysis observed in other F. graminearum strains and suggest a conserved ‘two‐speed’ recombination landscape. The consequences with regard to the evolutionary potential of this major fungal pathogen are also discussed. 相似文献
203.
Esmaeil Pagheh Jasem G. Marammazi Naser Agh Farzaneh Nouri Abolfazl Sepahdari Enric Gisbert Mansour Torfi Mozanzadeh 《Probiotics and antimicrobial proteins》2018,10(3):399-407
An 8-week study was conducted to evaluate three different diets supplemented with bovine lactoferrin (LF) at 0 (control), 800, and 1200 mg LF kg?1 diet on somatic growth, hemato-immunological parameters, antioxidant status, and digestive enzyme activities in silvery-black porgy (Sparidentex hasta) juveniles. Fish fed the 800 mg LF kg?1 diet had higher growth performance and feed utilization parameters than the other groups. Hematological and liver antioxidant parameters were not affected by dietary LF supplementation. Fish fed the 800 mg LF kg?1 diet had higher plasma lysozyme activity values than the other groups. Total protease activity was higher in fish fed LF-supplemented diets than the control group. Results indicated that diet supplemented with 800 mg kg?1 for 8 weeks enhanced somatic growth performance, lysozyme activity, and proteolytic digestive enzyme activities in S. hasta, as well as improving feed efficiency parameters like the protein efficiency and feed conversion ratios. 相似文献
204.
Changes in glucose 1,6-bisphosphate content in rat skeletal muscle during contraction. 总被引:3,自引:2,他引:1 下载免费PDF全文
Glucose 1,6-bisphosphate, fructose 2,6-bisphosphate, glycogen, lactate and other glycolytic metabolites were measured in rat gastrocnemius muscle, which was electrically stimulated in situ via the sciatic nerve. Both the frequency and the duration of stimulation were varied to obtain different rates of glycolysis. There was no apparent relationship between fructose 2,6-bisphosphate content and lactate accumulation in contracting muscle. In contrast, glucose 1,6-bisphosphate content increased with lactate concentration during contraction. It is suggested that the increase in glucose 1,6-bisphosphate could play a role in phosphofructokinase stimulation and in the activation of the glycolytic flux during muscle contraction. 相似文献
205.
Immunological properties of rat phosphoglycerate mutase isozymes 总被引:1,自引:0,他引:1
In mammalian tissues three phosphoglycerate mutase (D-phosphoglycerate 2,3-phosphomutase, EC 5.4.2.1) isozymes result from the homo-dimeric and hetero-dimeric combinations of two subunits (types M and B). Whereas rabbit antisera against type M subunit (purified from rat muscle) and against type BB isozyme (purified from rat brain) possessed a high degree of specificity, both antisera reacted with type BB and MM isozymes, as demonstrated by immunoneutralization and ELISA. Both the M subunit and B subunit were more immunoreactive than their respective dimeric isozymes. Subunits type M and B may possess common antigenic determinants, and some of these determinants may be sterically hindered in their dimeric structures. 相似文献
206.
Population structure from NOS genes correlates with geographical differences in coronary incidence across Europe 下载免费PDF全文
207.
Camilla Sguotti Christopher P. Lynam Bernardo García‐Carreras Jim R. Ellis Georg H. Engelhard 《Global Change Biology》2016,22(8):2729-2743
How have North Sea skate and shark assemblages changed since the early 20th century when bottom trawling became widespread, whilst their environment became increasingly impacted by fishing, climate change, habitat degradation and other anthropogenic pressures? This article examines long‐term changes in the distribution and occurrence of the elasmobranch assemblage of the southern North Sea, based on extensive historical time series (1902–2013) of fishery‐independent survey data. In general, larger species (thornback ray, tope, spurdog) exhibited long‐term declines, and the largest (common skate complex) became locally extirpated (as did angelshark). Smaller species increased (spotted and starry ray, lesser‐spotted dogfish) as did smooth‐hound, likely benefiting from greater resilience to fishing and/or climate change. This indicates a fundamental shift from historical dominance of larger, commercially valuable species to current prevalence of smaller, more productive species often of low commercial value. In recent years, however, some trends have reversed, with the (cold‐water associated) starry ray now declining and thornback ray increasing. This shift may be attributed to (i) fishing, including mechanised beam trawling introduced in the 1960s–1970s, and historical target fisheries for elasmobranchs; (ii) climate change, currently favouring warm‐water above cold‐water species; and (iii) habitat loss, including potential degradation of coastal and outer estuarine nursery habitats. The same anthropogenic pressures, here documented to have impacted North Sea elasmobranchs over the past century, are likewise impacting shelf seas worldwide and may increase in the future; therefore, parallel changes in elasmobranch communities in other regions are to be expected. 相似文献
208.
Dirk Sanders Rachel Kehoe FJ Frank van Veen Ailsa McLean H. Charles J. Godfray Marcel Dicke Rieta Gols Enric Frago 《Ecology letters》2016,19(7):789-799
Animals often engage in mutualistic associations with microorganisms that protect them from predation, parasitism or pathogen infection. Studies of these interactions in insects have mostly focussed on the direct effects of symbiont infection on natural enemies without studying community‐wide effects. Here, we explore the effect of a defensive symbiont on population dynamics and species extinctions in an experimental community composed of three aphid species and their associated specialist parasitoids. We found that introducing a bacterial symbiont with a protective (but not a non‐protective) phenotype into one aphid species led to it being able to escape from its natural enemy and increase in density. This changed the relative density of the three aphid species which resulted in the extinction of the two other parasitoid species. Our results show that defensive symbionts can cause extinction cascades in experimental communities and so may play a significant role in the stability of consumer‐herbivore communities in the field. 相似文献
209.
210.
H. Deckmyn L. Font C. Van Hemelen L.O. Carreras G. Defreyn J. Vermylen 《Life sciences》1983,33(15):1491-1497
Aortae from fetal or 3 weeks old rats produced very small amounts of PGI2, prostacyclin. This production increased from 4 weeks on, reaching adult values at about ten weeks. This maturation seemed to be predominantly determined by a change in the PGI2 synthetase system, rather than in arachidonic acid availability, phospholipase or cyclo-oxygenase activity. The anti-oxidant ascorbic acid stimulated prostacyclin production more strongly in adult than in young rat aortae. This finding suggests that the lower production of PGI2 by young tissues is not due to an enhanced inhibition of prostacyclin synthetase by lipid peroxides. 相似文献